THE EURYPTERIDA OF NEW YORK 419 
2 <A patch of integument with finely preserved sculpture, identical 
with that ascribed here to Stylonurus sp. a and represented on 
plate 53, figures 10-12 | 
3 Stylonuruscf. myops. Fragmentary medium sized cara- 
pace 
4 Coxa, probably belonging to Hughmiulleria 
5 omall telson of an Erettopterus 
182 B 23 has afforded a carapace showing the position of the eyes, 
and not distinguishable from Eurypterus maria. 
182 C 4x contains: | 
1 Eurypterus maria. Large and small carapaces 
Dolichopteruscf.otisius. Medium sized carapace 
Stylonurusmyops. Large and small carapaces 
Hughmilleriashawangunk. Large carapace 
Pterygotus cf. globiceps. Small carapace 
Nm BP W ND 
Swimming leg of a Pterygotus or Hughmilleria 
These faunules are so similar in their aspect and composition to that 
of the Shawangunk grit at Otisville, that, although they are too frag- 
mentary for a conclusive identification, it seems proper to infer that they 
belong to the same or an approximate horizon. It is, therefore, of much 
interest that Professor van Ingen has in the Swatara Gap section obtained 
good evidence that these beds which also correspond to the Shawangunk 
grit in lithology and stratigraphy, contain marine fossils of much greater 
age than the Salina. Professor van Ingen states that B&x of his section 
carries an apparently Clinton fauna, and Brgx a Rochester (or Lockport) 
fauna, while $2 C gx contains Arthrophycuscf. harlani Conrad. 
It will be noticed that the fairly good Shawangunk grit fauna, cited from 
Broh, comes from an horizon between these beds. 
Alternative hypotheses are suggested by this recent work; either 
that the Shawangunk grit is older than Salina age; or in view of the vast 
thickness of beds of like lithologic character in central Pennsylvania con- 
taining the eurypterid fauna of Otisville aspect, these rocks may represent 
